Dependency Injection in a DotNetCore Console Application

Application.cs

using System;
using Microsoft.Extensions.Options;

namespace MyConsoleApplication
{
	public class Application
	{
		private readonly IOptions<MySettings> _settings = null;

		public Application(IOptions<MySettings> mySettings)
		{
			// you can optionally do .Value but that makes it so updates in the JSON file won't reload in this instance
			_settings = mySettings;
		}

		protected MySettings Settings => _settings.Value;

		public bool Run()
		{
			if (!string.IsNullOrWhiteSpace(Settings.Name))
				Console.WriteLine($"Hello {Settings.Name}.");

			Console.WriteLine($"This application is {(Settings.IsCheesy ? "Cheesy" : "Not Cheesy")}");
			return true;
		}
	}
}

appsettings.Development.json

{
	"MySettings": {
		"IsCheesy": true,
		"Name": "Developer Man"
	}
}

appsettings.json

{
	"MySettings": {
		"IsCheesy": false,
		"Name": "George"
	}
}

MyConsoleApplication.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp2.1</TargetFramework>
  </PropertyGroup>

	<ItemGroup>
		<Content Include="appsettings.Development.json">
			<CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
		</Content>
		<Content Include="appsettings.json">
			<CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
		</Content>
	</ItemGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.Extensions.Configuration" Version="2.1.1" />
    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="2.1.1" />
    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="2.1.1" />
    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="2.1.1" />
    <PackageReference Include="Microsoft.Extensions.Options.ConfigurationExtensions" Version="2.1.1" />
  </ItemGroup>

</Project>

MySettings.cs

using System;

namespace MyConsoleApplication
{
	public class MySettings
	{
		public bool IsCheesy { get; set; }

		public string Name { get; set; }
	}
}

Program.cs

using System;
using System.IO;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;

namespace MyConsoleApplication
{
	internal class Program
	{
		private static void Main(string[] args)
		{
			try
			{
				string env = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT");

				if (string.IsNullOrWhiteSpace(env))
				{
					env = "Development";
				}

				var builder = new ConfigurationBuilder()
								.SetBasePath(Directory.GetCurrentDirectory())
								.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
								.AddJsonFile($"appsettings.{env}.json", optional: true, reloadOnChange: true)
								.AddEnvironmentVariables();

				IConfigurationRoot configuration = builder.Build();
				var services = new ServiceCollection();
				services.AddTransient<Application>();
				services.Configure<MySettings>(configuration.GetSection("MySettings"));

				var provider = services.BuildServiceProvider();

				var application = provider.GetService<Application>();
				application.Run();
			}
			finally
			{
				Console.WriteLine("\r\nPress any key to exit...");
				Console.ReadKey();
			}
		}
	}
}